Science blog reports research that demonstrates an ability among infants to use numbers between senses to match groups of people with the number of voices heard.
[Researchers] Jordan and Brannon presented seven-month-old infants with the voices oftwo or three women saying, 'Look.' At the same time, they showed the babies two video images: one with two women saying the word and the other with three women doing so. The researchers found that the babies spent significantly more time looking at the video image that matched the number of women talking. From that, the researchers concluded that the infants were transferring their perception of number across two different senses, sight and sound--which suggested, in turn, that babies have a truly abstract sense of numerical concepts.